Megasquirt users thread to discuss all things Squirty

[nuk1ear]

good to hear about the TPS, i wont stress about it too much then. I dunno what the PW is in ms cause i didnt read it off recently. Ill check it later on but i think its running way rich and the AFR correction is working too much at it. Ill do exactly what you said tho and ill warm it up, then switch it off, block the ICV off completely and get a good idle

[nuk1ear]

ok im basically certain that my stupid xf idle valve isnt working right, basically stuffed. Its only on or off. I tried every available frequency possible and from 0-60% PWM it does nothing (at lower frequencys 50-350 odd it will make all sorts of buzzing and ticking noises, but wont open lol), then 70-100% it will only be fully open.

Stupid junk. What other options are there? i head hyundais have a copy bosch one which works? anything else someone can suggest? Even a good stepper motor maybe cause its probably better lol?

[knightrous]

When I setup my MS2 on the old 16V 4AGE in my AW11, I didn't bother with idle valves or the cold start injector. I just adjusted the idle at the throttle plate and threw in some WUE to do the work of the cold start injector. Did over 7500km without any issues on that setup. When I put the DIYPNP onto the new 20V, I would have done similar, but it was easier to wire up the 3-wire idle valve then it was to adjust four ITB's to allow it to idle properly

Does your throttle body by chance have one of those vacuum idle up solenoids that some aircon units use to raise the idle? You could always wire that up to the MS3.

[nuk1ear]

no it has nothing. just a barb on it for an idle valve. If it had a valve on it, then i would use that instead. Anyway. Tomorrow i will disconnect the valve and block it off completely, ill just run nothing and try and find a new valve i guess

[thechuckster]

What other options are there? i head hyundais have a copy bosch one which works? anything else someone can suggest? Even a good stepper motor maybe cause its probably better lol?

the hyundai unit is a copy of the bosch item found in audi's etc.

has a fairly substantial-sized body and largish barbed inlet/outlets.

Not sure what frequency to drive it at but whatever the MS manual suggests for the bosch items would be a good start.

Stepper requires more wires-n-shit - personally I prefer the simplicity of a solenoid or PWM valve.

Also, while you're looking at the ECU, make sure the driver for the idle valve hasn't cooked. And check that you have a decent earth for the idle valve.


edit: have you cleaned the XF idle valve? The idle valve that came with my SR20 intake manifold was stuck solid with crap - had to completely pull it apart to get both the PWM and solenoid parts of it working (SR20 idle valve is cast block with three kinds of idle-control in it, a thermostat-driven part, simple solenoid and the PWM-driven bit - i deleted the thermostat part).

[nuk1ear]

as i said, its very clean, inside and out. I have also earthed everything to the block and then have another solid wire running from that earth to the body too. im not sure how much more i can clean it, its very sealed. Also, the idle valve never gets earthed, you put a 12v supply to it, the MS control pulls earth to control the valve.

[thechuckster]

sorry - should have gone back to your earlier post to see if you'd cleaned it. Sounds like time to ditch it and get a hyundai item.

[WDE_BDY]

For those interested, I contacted Trigger Wheels about the Mil Spec plugs to get some dimensions.

Sensors and connectors

Hi Callum,

For the 3-14pin connectors the mounting plate size is 30mm square. The 19pin ones are 37mm square. The 36, 50 and 65-pin ones are all 44mm square,

Regards,

Chris

Shall be placing an order I think, seem much more compact and way less ugly than the Delphi weatherpack bulkhead connector.

Weather Pack 22 position bulkhead connector kit DIYAutoTune.com

Callum

[timbosaurus]

Hey Callum,

Does their price include terminals?

Because I use genuine Tyco plastic screw-lock bulkheads, and they work out about $20 for the both connectors and 2 x backshells, and another $20 for 37 male terminals and 37 females.



These are 37 way, 13 amp connectors that use a ~36mm hole in the firewall.

I agree that the delphi weatherpack bulkheads are too freaking massive!

edit: so if theirs cost more than $50 delivered, or you'd like a better quality connector, hit me up

[WDE_BDY]

Very interested Timbo, you got some part numbers so I can see if I can source them in NZ? Otherwise would be keen get some from you.

Callum

[timbosaurus]

Mate, I get mine from a guy at I know from TYCO through work, they're not actually sold as a 'kit'. There'd be about 7 different components in a complete assembly, each with it's own P/N, MOQ etc - I haven't actually asked.

I can actually get a lot of cool things that way, in qty's that most companies wouldn't even talk to you for. Like coolant temp/TPS/Injector plugs/coil plugs/fuse boxs/etc.

Maybe I'll see if I can get a list together and become a toymods sponser section to help ppl get the odds and ends they need for MS setups.

[WDE_BDY]

In that case, happy to grab them from you. Just PM me some prices shipped to Gisborne, NZ and how to pay you (Paypal ok?) and we can go from there.

Callum

[nuk1ear]

can anyone else tell me their idle AFR on a 3sgte at running temp? Im struggling to get mine to idle nicely above 13 roughly at about 800/850rpm

[ballpencil]

can anyone else tell me their idle AFR on a 3sgte at running temp? Im struggling to get mine to idle nicely above 13 roughly at about 800/850rpm

this has been a question in my head as well.. in general, how do you adjust for best idle? do you go for the lowest vacuum at the desired rpm or is there a certain target AFR?

[thechuckster]

nuk1ear: what sized injectors? and are you running banked or batched injection? It could be that you're running out of injector time resolution to get any closer to stoich at idle - particularly if you've got more than one squirt per ignition event per cylinder.

As for tuning idle, I think one route is to:
- turn off any extras (idle speed control, AFR targeting, etc) so you're just running on the fuel & spark maps
- adjust your VE table to get your warm idle stable at your preferred revs and AFRs.
- adjust timing around that idle area to build in some stall prevention* and ease of warmup
- get your warm-up enrichment happy
- enable the close-loop idle control and tune to suit (will require multiple tests to get it right)
- enable AFR targeting in the idle range.

fwiw; I only ever enabled AFR closed loop for cruise and mild acceleration.


* for stall protection, I add fuel to the VE bins below where the idle should be (this simulates small touch on the throttle to lift revs slightly) and I adjust the timing (retard it a bit) to allow the engine to easily accel back into the preferred idle area, where the timing advance is fairly high. I end up with the warm idle bins having a VE that produces AFRs around stoich and those under that rev limit (tho at the same or higher MAP kpa value) having more fuel and less timing.